1. Field of the Invention
The present invention relates to an anomaly judgment device of a fuel cell system or the like and, more particularly, to a technology for improving the judgment accuracy.
2. Description of Related Art
Because a fuel cell system uses fuel gas, many means for judging system anomalies have been provided. For example, Japanese Patent Application Laid-Open No. 2004-139842 discloses a hydrogen leak sensing system that is constituted to sense a hydrogen leak by means of a hydrogen leak sensor in cases where the vehicle speed is less than a predetermined value and to sense a hydrogen leak based on the correlation between a power generating current theoretical value for the fuel cell which is calculated in accordance with quantity of hydrogen supplied to the fuel cell and the actual power generating current value of the fuel cell in cases where the vehicle speed is equal to or more than a predetermined value. Furthermore, Japanese Patent Application Laid-Open No. 2003-308866 discloses a gas leak sensing device that is constituted to detect the enclosed region internal pressure of a fuel gas circulatory supply system by means of a pressure gauge and which, in cases where the detection result of the pressure gauge indicates a drop in pressure at a speed equal to or more than a given reference, judges that a fuel gas leak has been produced.
All the prior art involves devices that compare a measured value from some kind of detection device with a comparison value and ultimately judge a hydrogen leak in accordance with the comparison result.